Clouds Open

The sound and fury of the Java storm caught many of us off-guard. And why not? It came from an unlikely source, was delivered in an unconventional vehicle, and defied conventional wisdom regarding performance of interpreted languages. Other than the language, nothing about Java was conventional at all, including the size of the explosion. In retrospect, you can look back and see just how well it filled a void. Figure 2-3 shows the many ingredients that come together to form the perfect storm.

Figure 2-3. Many forces formed the combined ingredients that led to a perfect storm

New Economics

The jet stream that powered this storm emerged from a series of standards: TCP/IP, HTTP, URI, and HTML. The Internet gathered steam, and Sun took full advantage with Java. The Internet was everywhere. Java was cool. The Java developers quickly built the API set that would allow developers to code for the Internet, including TCP/IP APIs for communication, and applets for building user interfaces that you could embed in a browser. JDBC allowed database access.

The perfect combination formed by the relationship between Netscape Navigator and Java drove each company to new heights. Through Netscape, Sun was able to put Java in front of an incredible number of developers, nearly instantaneously. Through Java, Netscape could showcase smart applications that looked cool, and were simultaneously practical. The Navigator/Java combination seemingly solved the most critical problems of client-server computing: management and distribution. If you could install a browser, you could then automatically distribute any application that you wanted through the browser. Java had the perfect economic conditions for success. Java found an important ally in the bean counters that liked the manageability of the green screen, but the productivity and usability of the fat client.

Customers wanted solutions, and Sun realized that Java would give them what they wanted. Sun immediately saw the opportunity it faced. With the open standards around the Internet and the Java language powering it, Solaris on Sun servers would be a compelling, and even hip, alternative. Above all, Java made Sun safe. Because its virtual machine ran in a browser and on many different operating systems, some hard decisions didn't seem so hard. You could try out a deployment scenario. If you didn't like it, you could just move on.

The new jet stream was in position to feed power to the growing storm.

C++ on Prozac

When Lucene founder Doug Cutting called Java C++ on Prozac,[*] I immediately liked the comparison. Because of its C++ syntax, Java found an impressive waiting community of developers looking for a solution. They moved to add a hip Java, and Internet experience, to their resumes. They stayed because they liked it. Java had most of the benefits of C++, without the problems. The similarities of the languages made it easy to learn. And Java was liberating, for many reasons:

Architecture

The benefits of Java went beyond economics and C++. I can still vaguely remember the first sentence that I saw describing Java. Sun said it was a portable, safe, secure, object-oriented, distributed programming language for the Internet. Those words were all buzzwords of the time. For C++ developers, Java underpinnings made significant strides:

The JVM allowed unprecedented portability. Many experts believe that the JVM, and not the language, is the most important feature of Java. Sun marketed this capability brilliantly with the acronym WORA. Java developers the world over recognize those letters as standing for Write Once, Run Anywhere.

Java published the byte code specification for the JVM. People who want to build their own JVM or build a language on the existing JVM standard can do so, or even modify byte codes of existing applications. Frameworks like JDO do modify byte code with great success.

While C++ allowed unrestricted access to application memory, Java restricted access to one area of the JVM called the sandbox. Even today, you see very few exploitations of Java security.

The Java metamodel, made up of the class objects that describe types in Java, allowed sophisticated reflective programming. Though it's a little awkward, the capabilities of Java extend far beyond the basic capabilities of C++. The Java metamodel enables frameworks that increase transparency, like Hibernate (persistence) and Spring (services such as remoting and transactions).

The fathers of Java saw the importance of security, and baked it into the language. Java introduced a generation of programmers to the term sandbox , which limited the scope and destructive power of applications.

Java had improved packaging and extensibility. You could effectively drop in extensions to Java that transparently added to capabilities of a language. You could use different types of archives to package and distribute code.

Both the low-level grunts and high-level architects had something to love. Businesspeople had a motivation to move. At this point, if all else had failed, Java would have been a successful language. But it didn't fail. The winds just kept picking up speed, and the storm started feeding on itself.